In a vehicle transmission including frictional disk-type side clutches, frictional disk-type side brakes have been provided in a series arrangement with the side clutches.
A typical example is disclosed in Japanese Utility Model Publication No. 60-23253 in which left and right clutch shafts are disposed co-axially with an output shaft of speed-change mechanism at opposite sides of the output shaft. To one and the other ends of the output shafts are fixedly secured left and right clutch housings which extend towards left and right clutch shafts, respectively. Each of the left and right side clutches is fashioned into a frictional disk-type having opposite sets of frictional elements which are slidably but non-rotatably supported respectively by each clutch housing and by each of the left and right clutch shafts. At the outer sides of such left and right clutches are disposed left and right side brakes of a frictional disk type each of which is fashioned to have opposite sets of frictional elements supported respectively by a transmission casing and by each clutch shaft.
The structure referred to above requires a lengthy transmission casing due to separate clutch shafts disposed at opposite sides of the output shaft and due to the side by side arrangement of respective side clutches and side brakes which arrangement requires prolonged clutch shafts.
For solving such problem, a side brake is considered which is disposed within a space around the clutch housing of a frictional disk-type side clutch so as to brake the clutch housing. However, when such side clutch is fashioned into a frictional disk-type which permits an easy control of braking force, it is required to employ frictional plates or elements of a large diameter as the ones to be supported by a transmission casing. Such frictional plates or elements require a large brake case on an inner wall of the transmission casing so that the size of transmission casing is enlarged correspondingly.